Health In Scotland 2001

Health in Scotland 2001

CHRONIC FATIGUE SYNDROME (CFS/ME)

CFS/ME is a relatively common clinical condition affecting approximately 20,000 people in Scotland per year. It can cause profound, often prolonged, illness and disability, with a substantial impact on both the individual and the family. All age groups are affected, including children. Hitherto patients and carers often encountered a lack of understanding from healthcare professionals. This seemed to stem from an inadequate awareness and little understanding of what the illness involved, often reflected in the general population. As a result the treatment and care has been patchy and inconsistent, compounding the difficulties individuals have experienced. There has been a paucity of good research evidence and research investment for a serious clinical problem. These were the findings of a working group set up in 1998 by the Chief Medical Officer (England) at which the Scottish Executive Health Department was represented.

It is clear that CFS/ME is not a purely physical disorder. It severely affects the morale and ability to cope of those who experience it. Neither is it a psychological condition alone, because of the many genuine and varied physical signs and symptoms associated with the disorder. So far there is an evidence base for psychological interventions based on cognitive behaviour therapy and graded task assignment, but little else. There is much left undiscovered so far with more research urgently needed into the optimum provision of care.

A short life action group has been established during 2002 in Scotland and started work to translate the CMO (England's) report into a Scottish context. People with personal experience of CFS/ME, those who care for them, and representatives of voluntary organisations will be included as well as health and social care professionals.

In contrast, the uptake of measles, mumps and rubella (MMR) vaccine has decreased markedly in 2001. This has also been the trend for England, Wales and Northern Ireland, although rates for Scotland continue to compare favourably.

The figure for MMR vaccine uptake in Scotland for all children reaching their second birthday in 2001 was 88.5%. Pre-school vaccination uptake rates for 2001 indicate that 92.7% of children received fourth doses of diphtheria and tetanus vaccines by their sixth birthday, 92.9% a fourth dose of polio vaccine and 88.3% a second dose of MMR.

There were no reports of diphtheria, tetanus or poliomyelitis in Scotland in 2001, continuing to represent long-term successes in immunisation. The overall number of notifications and laboratory reports for pertussis remain relatively unchanged (Table 2.3). Analysis of hospital discharge data by ISD in 2001 showed that in recent years over 70% of patients hospitalised with pertussis infection were under the age of 6 months. There is evidence that these infants may be catching pertussis from older siblings, or possibly parents. An acellular pertussis booster for pre-school children was therefore planned in 2001, to be introduced into the routine childhood immunisation schedule from January 2002.

The number of notifications and laboratory reports received for measles, mumps and rubella continued to decrease in 2001 (Table 2.3), compared to previous years. Of particular note, for the first year on record, there were no laboratory reports received for measles. However, measles cases occurred in the early months of 2002, which emphasises that the continued control of measles, mumps and rubella can only be sustained by high levels of vaccine uptake in all communities throughout Scotland. MMR continues to be the safest way to protect children against these diseases. A discussion pack was published by the Health Education Board for Scotland, in collaboration with the Scottish Executive and SCIEH, in September 2001 to help parents and health professionals review the evidence about MMR and will help provide the basis for informed decision-making. The Scottish Executive also established an MMR Expert Group, in August 2001, to look at a range of issues flowing from the Health and Community Care Committee's report on MMR and examine evidence relating to the apparent rise in the incidence of autism among children.

Thirteen laboratory reports were received for invasive Haemophilus influenzae b (Hib) disease in 2001 (Table 2.3). Hib vaccine was introduced in 1992 and this is the highest annual number of laboratory reports since 1993. Reasons for the increase are still unclear, but the increase has been reflected throughout the UK and continue to be investigated, through collaboration in enhanced UK surveillance.

Meningococcal Infection

Following the dramatic decline of Haemophilus influenzae b (Hib) meningitis by a successful vaccination campaign in the early 1990s, Neisseria meningitidis or the "meningococcus" is now the leading cause of bacterial meningitis in the UK, with around 300-350 notified cases of invasive disease (principally meningitis and septicaemia) per year in Scotland. In spite of significant recent improvements in the early recognition and treatment of meningococcal disease, it continues to cause significant mortality (around 6% case fatality) and long-term morbidity. Over 90% of cases are caused by serogroups B and C, with very small numbers from rarer groups such as Y or W135.

The late 1990s saw a steep rise in notifications of meningococcal disease in Scotland after around 20 years of relative stability. The conjugate Group C meningococcal vaccine (MenC) was introduced in the winter of 1999 in a phased programme, at a point where Group C infections accounted for around 55% of typed cases. The evidence to date suggests a very successful impact on the burden of Group C disease. Surveillance data collated by SCIEH and the Scottish Meningococcal & Pneumococcal Reference Laboratory (SMPRL) show an absolute decline in numbers of cases (355 in 2000 to 271 in 2001, a decrease of almost one quarter) and a sharp reduction in cases of Group C infection in the vaccinated age groups following introduction of MenC vaccine (Figure 2.8). Only a single case of Group C infection has been reported to date in a fully vaccinated individual, emphasising the effectiveness of the vaccine. Although meningococcal disease remains predominantly a disease of very young children, a shift towards older age groups combined with the much higher mortality in adults remains a cause for concern. With seven out of the ten deaths in young adults in 2001 known to be a result of group C infection, the extension of the MenC vaccination campaign to those aged between 20 and 24 in January 2002 should help further reduce mortality, as well as overall incidence, in the under 25s.

Fig. 2.8 Meningococcal Infections by Group, 1998 to 2001

N/K - Group not known

Influenza

The flu season of winter 2000-2001 was exceptionally mild, in that the rate of consultations for flu-like illness barely exceeded the baseline activity threshold of 50 GP consultations per 100,000 population. This represents the lowest clinical reporting level since the GP-based "Flu-spotter" scheme began in 1971. Laboratory data did, however, indicate that there was a moderate amount of influenza B in circulation with reports characteristically being received well into the new year, long after influenza A had become sporadic.

Winter 2000-2001 was also the first year of the new enhanced surveillance scheme for influenza and other seasonal viral infections. The Scottish Enhanced Respiratory Viral Surveillance Scheme (SERVIS) is co-ordinated by SCIEH and collects weekly consultation data in real time on respiratory infections from over half of Scotland's computerised Continuous Morbidity Recording (CMR) practices. Although the population sample covered by SERVIS is around 5% compared with the 10% for the traditional flu-spotter network, it is more representative geographically and for the first time provides age and sex information on those consulting for both influenza-like illness (ILI) and acute respiratory infection (ARI). This information is combined with a linked virological testing programme (a multiplex PCR technique, carried out by the Glasgow Regional Virus Laboratory), which, for the first time in 2000-2001, provided diagnostic data on other seasonal viruses which may also contribute to ILI and ARI consultations. Although based on a limited number of swab results, it was still possible to discern sequential peaks in the seasonal activity of picornavirus, RSV, influenza type A and influenza type B (Figure 2.9).

The SERVIS scheme is one of the most advanced and sophisticated routine influenza surveillance projects in Europe and together with flu spotter data, provided weekly information and advice for NHS Boards and Trusts throughout the winter. SCIEH also collated GP practice data on the take-up of flu vaccine in the last 3 months of 2001, in order to monitor progress towards the target of 65% uptake in people aged 65 and over.

Tuberculosis

The Enhanced Surveillance of Mycobacterial Infections (ESMI) scheme was implemented in January 2000, and is supplying continuous detailed information on tuberculosis in Scotland for the first time. The epidemiology of TB in Scotland is different from that elsewhere in the UK in several important respects, principally in that overall numbers are in slow decline, and that the majority of cases (around 85%) are indigenous rather than in persons born outside the UK. This contrasts with the situation in England and Wales, where numbers are increasing (particularly in London) and only around 40% of cases are UK-born. The detailed information held by ESMI will facilitate a number of approaches to tuberculosis control (and eventual elimination) through population or risk-group targeting and clinical audit. Risk factor analysis shows alcohol abuse to be the leading issue by a wide margin (50/85 with recorded risk factors), followed by healthcare workers (15/85), with smaller numbers of immunosuppressed people, homeless and hostel dwellers, and asylum seekers. There are already other areas indicated by ESMI which may repay further examination: for example, of the 360 Scottish cases reported to ESMI in 2001, 24 (8%) had been symptomatic for longer than 6 months at diagnosis. Overall, the data for 2001 (provisional) show little change from those collected for 2000. The value of the ESMI resource will increase as more data are collected in the forthcoming years.

Blood-borne Viruses and Sexually Transmitted Infections

HIV Infection

In 2001, 173 cases of HIV were reported to SCIEH; this was the highest annual total since 1997 and its excess of approximately 20 cases over the totals for each of the previous 2 years can be explained by the continuing increase in the numbers of diagnoses among heterosexuals who have acquired their HIV abroad, particularly in Africa (Figure 2.10). It is estimated that between one-third and one-fifth of such imported infections occur in Scottish travellers. The findings of a new surveillance initiative, established in 2001, to subtype the virus of each newly diagnosed individual, indicates some diffusion of African and Asian HIV strains among heterosexuals, indigenous to Scotland, who have declared no exposure abroad. While the transmission of HIV among injecting drug users (IDUs) remains rare and that among gay men is stable or in slight decline, the greatest HIV risk to the general population is posed by unprotected sexual intercourse among travellers who travel between Scotland and countries with a high prevalence of HIV. Accordingly, SCIEH and the Health Education Board for Scotland are increasing their efforts to improve public awareness of this danger.

Fig. 2.10 HIV reports, Scotland; by risk and year of report

In 2001, the Scottish Executive's Expert Group on the Treatment and Care of HIV and AIDS in Scotland (Chair: Dr Andrew Fraser, DCMO) published its findings. As at June 2001, 1,300 persons with HIV were in clinical care, of whom 75% were being administered Highly Active Antiretroviral Therapy (HAART). There was no evidence of any inequity in access to, or administration of, HAART, vis-à-vis area of residence or HIV risk status. It is predicted that the numbers of persons in Scotland receiving HAART will increase annually during 2001-2004 by about 60 (Table 2.4); the majority of new cases on treatment will reside in Lothian and Greater Glasgow NHS Boards. The increases reflect an increasing prevalence of known HIV infected persons in Scotland, mainly as a consequence of the anticipated large discrepancy between the annual numbers of persons diagnosed with HIV (150-180) and the annual numbers of deaths from HIV (30-70).

Table 2.4 Observed data for 2000 and predictions for 2001-2004: All Scotland

Year

Under CD4 Monitoring at end of year

On HAART

Not on HAART

Eligible for HAART

N

Annual Increase

2000 observed

1210

863

347

1004

2001 predicted

1308

922

+59

386

1073

2002 predicted

1403

983

+61

420

1144

2003 predicted

1489

1041

+58

448

1210

2004 predicted

1571

1099

+58

472

1276

Hepatitis C Virus (HCV) Infection

During January-June 2001, 890 persons in Scotland were diagnosed with HCV; this rate of diagnosis is consistent with that seen during the previous 3 years and brings the total number of known cases to 12,680. Preliminary estimates indicate that a further 20-30,000 infected persons in Scotland remain undiagnosed. The great majority of the 890 recent diagnoses are IDUs who are well represented in almost every Scottish NHS Board. A Scottish Executive sponsored study, undertaken by the Centre for Drug Use Research, University of Glasgow, and SCIEH in 2001, estimated high prevalences of HCV among IDUs in most health boards and that 10,000 of Scotland's 22,800 current IDUs were infected (Table 2.5). There is evidence that harm-reduction measures - namely, needle and syringe exchange and methadone therapy - have led to a reduction in HCV transmission among IDUs but early findings from a CSO-funded study, conducted in 2001, of recent initiates to injecting in Glasgow, indicate that the incidence of HCV remains extremely high.

In early 2001, a Scottish Needs Assessment Programme workshop on "HCV in IDUs" identified the need to evaluate existing and implement new interventions, to prevent infection among this population; the complexity of the challenge is demonstrated by the observation, during the late 1990s, that the frequency of needle and syringe sharing increased in certain areas where there had been a concomitant increase in harm reduction service provision. The Scottish Executive's Effective Intervention Unit has since released a "call for research" into interventions designed to reduce the incidence of HCV among IDUs.

Hepatitis B Virus (HBV) Infection

In 2001, SCIEH received 357 new reports of HBV; while this total was almost identical to that seen in 2000, there was a noticeable shift in the geographical distribution of infection. A marked decline in reports from Grampian - 54 in 2001 compared to 100 in 2000 and 114 in 1999 - was offset by small increases in Greater Glasgow and Lothian, and a dramatic increase in Lanarkshire (25 in 2000 to 43 in 2001). These observations reflect changing patterns in the spread of HBV among IDU populations. In the context of a resurgence of HBV among IDUs throughout Scotland in recent years, their immunisation against this infection, as recommended by the Health Departments, is strongly encouraged. Indeed, vaccination against both HBV and HAV (Hepatitis A virus) should be considered; in Grampian, during late 2000 and much of 2001, HAV was highly incident among IDUs. A case control study was conducted to ascertain if this virus had spread through the sharing of injecting equipment or through the traditional oro-faecal route; the results are awaited.

Example from Grampian: Blood-borne Pathogens

Preventing the spread of blood-borne pathogens, namely Hepatitis B, Hepatitis C and human immunodeficiency virus (HIV) is a local priority. There are currently outbreaks of Hepatitis A and B, primarily amongst drug injecting users in Aberdeen City. In Scotland, Grampian is second only to Glasgow for the rate at which people are diagnosed as Hepatitis C antibody positive.

The multi-agency Grampian blood-borne pathogen strategy aims to:

raise awareness of these infections

reduce the spread and

ensure effective investigation and management of patients affected.

Implementation of the strategy has included awareness campaigns targeting high risk groups, specialist blood-borne pathogen posts to provide timely advice and Hepatitis B immunisation and increased provision and access to needles and syringes.

Sexually Transmitted Infections, other than HIV

For sexually transmitted infections (other than HIV), the dominant observation in 2001 was the continuing rise in the numbers of Chlamydia diagnoses; 7,149 females and 2,772 males, representing 36% and 50% increases on the previous year's figures, were recorded by Chlamydia testing laboratories. The upward trend in diagnosis has been evident throughout the country since 1997. The increases are considered to reflect increased high risk sexual behaviour among general populations of young male and female heterosexuals, improvements in the sensitivity of the diagnostic test and major increases in screening activity, particularly among females. The large discrepancy between the numbers of male and female diagnoses is explained by the paucity of screening activity among asymptomatic males outside the Genitourinary Medicine Clinic setting. Large variations in the incidence of Chlamydia detection among NHS boards in 2001 suggest that screening practice varies considerably at a geographical as well as a gender level.

The finding that the incidence of Chlamydia diagnosis among both males and females in Highland exceeds rates in most other health boards, supports the view that this infection knows no boundaries.

In 2001, the incidence of gonorrhoea, which had been increasing since 1997, plateaued; the majority of the 817 cases diagnosed in 2001 were male and residents of Lothian and Greater Glasgow, observations which, in part, reflect the higher proportion of gay male cases in these areas. In contrast to Chlamydia, gonorrhoea is generally confined to relatively small sexual networks comprising either gay men or heterosexual men and women in areas of deprivation; however, there are signs to indicate that gonorrhoea is beginning to spread into the wider heterosexual population.

Work is proceeding on a second health strategy for Scotland. Its research stage has now been completed. This includes a review of current sexual health services in Scotland and an analysis of the Scottish sample in the recent National Survey of Sexual Attitudes and Lifestyles. That work will inform the further development of the strategy which will address (among other matters) recent increases in the incidence of Sexually Transmitted Infections and the still high rate of unintended teenage pregnancies in Scotland.

Healthcare Associated Infection

It is estimated that any one time 9% of hospital in-patients has a healthcare associated infection (HAI). HAI may include surgical site infections, urinary tract infections, respiratory tract infection, infections due to specified micro-organisms such as methicillin-resistant Staphylococcus aureus (MRSA) or Clostridium difficile. The Report of the National Audit Office in England The Management and Control of Hospital Acquired Infection (2000) estimated that 15% of HAI can be prevented with appropriate infection control resources. An estimate of the cost of HAI to the health service in Scotland prepared in 1999 has been updated (A Walker 2001) in the light of newly available data and puts the costs as at least 101 million.

Effective control of HAI requires robust surveillance of HAI, infection control and risk management processes embedded within trusts' organisational structures. During 2001, the Scottish Executive Health Department has agreed the measures that are to be put in place by trusts in order that HAI can be effectively contained, the operation of these processes monitored by the SEHD and information about the way the NHS deals with HAI made available to professionals and the public.

National and Local Surveillance of Healthcare Associated Infection

Few robust data on the incidence of healthcare associated infection (HAI) are available and much of the existing data do not permit comparisons to be made of the incidence of these infections in different hospitals partly because of differences in definitions and in methods of measuring infection and partly because of differences in the risk to patients of HAI as a result of their own vulnerability or in the hospital environments.

The urgent need to obtain robust data on HAI incidence has been addressed by the Advisory Group on Infection's Subgroup on Surveillance of HAI and Antimicrobial Resistance. The recommendations of the subgroup on HAI surveillance were adopted by the Scottish Executive Health Department and these were conveyed to trusts in Health Department Letter (2001) 57. This HDL requires trusts to use national standardised methodologies to undertake local surveillance:

trusts are required to implement surveillance of surgical site infection (SSI) following two surgical procedures selected from a short list and provide data for national reporting by April 2003

trusts undertaking neurosurgery are required to implement surveillance of SSI after neurosurgical procedures

national reporting of MRSA bacteraemias is to be in place by April 2002.

SCIEH has been funded to collaborate with Trusts in the implementation of HAI surveillance by developing standardised national methodologies, facilitating and assisting with local implementation and collating the national datasets. Early in 2002 a national protocol for surgical site infection was circulated to trusts and development of MRSA bacteraemia reporting was well underway in preparation for the publication in April 2002.

A National HAI Surveillance Steering Group has been set up with the brief to oversee and advise the SEHD on the implementation of the national programme of surveillance of HAI in Scotland, to monitor this and to report on progress. One area of surveillance requiring particular attention is the surveillance of surgical site infections in the period after the patient has been discharged from hospital. Patients are no longer under direct medical supervision and accurate ascertainment of wound infection according to a standard definition is not straightforward. There is no international consensus about the best way to obtain robust data on the incidence of post discharge surgical site infections. A number of pilot projects to examine and evaluate different methods are being implemented.

Managing the Risk of Healthcare Associated Infection

Health Department Letter (2001) 53 "Managing the Risk of Healthcare Associated Infection in NHSScotland", also published in June and based on the recommendations of a report of a joint SEHD and NHSScotland Working Group, requires trusts to address the risks of healthcare associated infection. Responsibility for healthcare associated infection is placed with the Trusts' Infection Control Committees. Trusts are required to develop training and development programmes for staff, to ensure that the infections control teams are sufficient in personnel and resources to take on the workload associated with risk management including the production of annual infection control programmes and to undertake self-assessment of their performance in risk management of healthcare associated infection. Their annual reports and the results of self-assessment against the Infection Control and other relevant standards will be subject to appraisal by the Clinical Standards Board for Scotland (CSBS) against the CSBS's Standards for Infection Control published in December 2001.

Antimicrobial Resistance

Currently surveillance of antibiotic resistance in medical practice includes reporting of methicillin-resistant Staphylococcus aureus (MRSA), voluntary reporting to SCIEH by 15 laboratories of qualitative data on resistance based on 15 "alert organism/antibiotic combinations" and qualitative data on resistance in Enterobacteriacea. Data on MRSA in Scotland have been collated by SCIEH from the routine reporting to SCIEH by laboratories which has been in place since 1971. Figure 2.12 shows the marked increase since 1998 in MRSA bacteraemias reported to SCIEH. There has not been much change in the same period in reports of methicillin-sensitive Staphylococcus aureus (MSSA). Nationally routine quarterly reporting of data on MRSA is to be introduced from April 2002.

Recommendations for national surveillance of antimicrobial resistance are being prepared by the Advisory Group on Infections' Subgroup on Surveillance of Healthcare Associated Infection and Antimicrobial Resistance which has been meeting during 2001. The subgroup has been considering surveillance in medical, dental and veterinary practice. Their report, which will be available in the first half of 2002, will address the issue of national reporting of routinely generated data, the lack of standardisation of laboratory protocols for testing and reporting (including quantitative reporting of resistance), resistance data from reference laboratories, further development of MRSA surveillance and development of surveillance of antibiotic resistance and prescribing in intensive care units. Proposals for surveillance in dental practice and the issue of surveillance of antibiotic resistance in veterinary practice will also be considered.

Fig. 2.12 Trends in MSSA and MRSA bacteraemia in Scotland, 1992 to 2001

Deliberate Release of Biological, Chemical or Radiological Materials

The events of 11 September 2001 and the deliberate release of anthrax in the USA have focused attention on the necessity for preparedness by health services, in collaboration with other agencies, for events caused by deliberate release of biological, chemical or radiological materials. While the overall control of responses to such an incident are at UK level, there is a necessity for NHSScotland to ensure the establishment of local and national expertise, resources and training to secure safe management of response to an incident, particularly at the early stages. To this end, the Scottish Executive Health Department issued guidance Deliberate Release of Biological and Chemical Agents in Scotland as the core Scottish document for public health action.

One of the effects of the acute global interest in bioterrorism has been the development of documentation (e.g. scientific and technical information, national and local policies and strategies, interagency guidance). SCIEH has undertaken to provide access to the latest versions of key documentation for public health action and has also been very much involved in surveillance activities. The issue of bioterrorism is one that is unavoidably high on the agenda for the foreseeable future and that will require a continuing strategic programme of awareness and preparation.

The events of 11 September also highlighted the importance of ensuring that the health service in particular but the emergency services in general, were able to cope with the potential deliberate release of hazardous chemical agents. Immediate efforts were directed at identifying the existing capabilities, training needs and resources within Scotland. This resulted in significant additional resources being allocated for specialist equipment, to enhance the ability of Ambulance and A&E services if called upon to handle contaminated casualties or to decontaminate people exposed to chemical agents. In addition research was undertaken by SCIEH to determine the availability of equipment capable of detecting the presence of chemical agents and also the capability of the health service to screen patients for hazardous chemical exposure. This provided useful baseline information for planning future needs and capability levels.

Training

A series of training events were held aimed primarily at NHS staff to raise awareness of issues associated with deliberate release scenarios. Multi-agency events were also held in order to stress the importance of co-operation and joint working between the NHS and the Emergency Services.

An explicit aim of the training was to enable NHS Boards to identify local issues relating to planning, capability and readiness which required enhancement to meet the challenges posed by a deliberate biological, chemical or radioactive agent release within their locality.

ENVIRONMENTAL HEALTH

Public perception of risk was a major factor in determining the environmental health topics which generated attention in 2001.

Foot and Mouth Disease

Concerns regarding potential environmental health threats focused heavily on foot and mouth disease in 2001. The outbreak created a significant environmental burden, mainly in Dumfries and Galloway, in terms of ensuring the safe disposal of the animal remains. The subject also generated public anxiety. These concerns focused on the potential health impact of exposure to the smoke plumes from pyres and to the possible long-term contamination of soil and water sources from the burial of remains and pyre ash. Considerable efforts were made by a wide variety of UK government and local agencies, including Dumfries and Galloway Council and NHS Board, DEFRA, SEPA, SEERAD, SEHD and SCIEH, to undertake environmental risk assessment and monitoring. The reassuring conclusion of studies carried out in Dumfries and Galloway on the risk associated with pyre smoke, was that there was no significant threat to the health of the local population from production of dioxins or other hazardous substances. Monitoring of groundwater and public supplies will continue for some time but evidence to date has not confirmed any significant problems in drinking water. On behalf of SEHD, SCIEH developed a website to provide a single access route to the environmental monitoring data for Scotland ( www.fmd-enviroimpact.scieh.scot.nhs.uk). This continues to provide information on the work done by the relevant agencies and access to all existing monitoring data for Scotland.

chemical accidents and spillages including chlorine at a leisure centre

depleted uranium used in munitions testing near the Solway Firth

mobile phone masts and "electrosensitive" people.

Two issues in particular were the subject of planning enquiries, the outcomes of which both underlined the growing recognition of the relevance of environmental health issues in determining the planning decisions.

New Sewage Treatment Plant

Concerns about odours and possible risks to public health were raised by local residents, objecting to the siting of a new sewage treatment plant next to a water reservoir on the Island of Bute. The resulting planning enquiry decision found in favour of the local community objections and required the then West of Scotland Water to include covers in the plans for the sewage treatment tanks at the new plant, to minimise odours and to reduce the possibility of airborne release of pathogenic organisms to the surrounding population.

New Open-cast Coal Mine

In Lanarkshire, a proposal for a major new open-cast coal mining project was rejected by a planning enquiry and this was upheld subsequently following an appeal. In this case the local health concerns related to the potential for generating excessive amounts of fine particulate matter (PM 10) from the excavation of soil and materials and production of diesel emission particles by the heavy machinery and transport equipment, which in turn might pose a health threat to the local population.

The "Precautionary Approach"

The Precautionary Approach (or Principle) is the term used to define situations where it is accepted that even in the absence of definitive evidence, the potential for adverse health effects alone can justify a course of action or a refusal to allow a new development.

In both situations the planning system adopted a "precautionary approach" to potential environmental health threats. This marked a significant shift in the weight attributed to potential, as opposed to definitely proven, health threats. These represent landmark decisions in that they establish precedents for the use of the precautionary principle in assessing the potential health impact of new developments that have environmental impacts.

2001 also saw the introduction of new legislation in Scotland, concerning how proposals for new industrial developments gain approval by SEPA, known by the acronym PPC, standing for Pollution Prevention and Control. NHS Boards became statutory consultees and now have the right to comment and contribute to the assessment of possible health impacts of new developments, which might emit potentially harmful substances to the local environment. This has provided the opportunity to request modifications to proposals to further minimise health risks. SCIEH hosted a training seminar on PPC and developed a guide together with a proforma to assist NHS Board consultees in analysing and commenting on local developments.

As with other environmental health issues, the public perception of the hazards posed by local industries may differ from the views of public health professionals, who base their responses on interpreting available scientific knowledge. Professionals commonly approach issues using the traditional concepts of risk assessment and the "source-pathway-receptor" model, as means of determining the plausibility of any association between an environmental agent and an alleged health effect. The response of the public is frequently based on heartfelt but often poorly specified concerns regarding the possibility of adverse effects associated with often highly visible or controversial developments, such as the introduction of genetically modified crops. The challenge to professionals for the future lies in helping the public to understand better the rationale for the scientific approach to evaluating hazards and in explaining risk assessment in terms that can be understood and accepted but which also address genuine public concerns.